The cornea is the most densely innervated tissue in humans. Peripheral corneal nerves regenerate follow injury. Our hypothesis is that VEGF is a critical determinant of corneal nerve regeneration after injury and that the signaling pathways which mediate neurogenesis are distinct from those which mediate angiogenesis. Aim A will characterize the expression of VEGF and VEGF receptors and identify the receptors which mediate VEGF-dependent neurogenesis in vitro and in vivo. Aim B will characterize effect of VEGF on the regeneration of nerves in 2 injury models, while Aim C will investigate the pathways responsible for these effects. We will analyze whether there exists a differential activation of VEGF mediated neurogenesis following different injuries.